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Archwire
An archwire in orthodontics is a wire conforming to the alveolar or dental arch that can be used with dental braces as a source of force in correcting irregularities in the position of the teeth. An archwire can also be used to maintain existing dental positions; in this case it has a retentive purpose. Orthodontic archwires may be fabricated from several alloys, most commonly stainless steel, nickel-titanium alloy (NiTi), and beta-titanium alloy (composed primarily of titanium and molybdenum). Types Noble Metal alloy Noble metals such as gold, platinum, iridium, silver and their alloys were used early on in the field of Orthodontics because of their good corrosion resistance. Some of the other qualities that these alloys had were high ductility, variable stiffness (with heat), high resilience and ease of soldering. Disadvantages of these alloys were: Less elasticity, less tensile strength and greater cost. Composition of both platinum and palladium raised the melting po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orthodontics
Orthodontics is a dentistry specialty that addresses the diagnosis, prevention, management, and correction of mal-positioned teeth and jaws, and misaligned bite patterns. It may also address the modification of facial growth, known as dentofacial orthopedics. Abnormal alignment of the teeth and jaws is very common. Nearly 50% of the developed world's population, according to the American Association of Orthodontics, has malocclusions severe enough to benefit from orthodontic treatment: although this figure decreases to less than 10% according to the same AAO statement when referring to medically necessary orthodontics. However, conclusive scientific evidence for the health benefits of orthodontic treatment is lacking, although patients with completed orthodontic treatment have reported a higher quality of life than that of untreated patients undergoing orthodontic treatment. Treatment may require several months to a few years, and entails using dental braces and other appliances t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dental Braces
Dental braces (also known as braces, orthodontic cases, or cases) are devices used in orthodontics that align and straighten teeth and help position them with regard to a person's bite, while also aiming to improve dental health. They are often used to correct underbites, as well as malocclusions, overbites, open bites, gaps, deep bites, cross bites, crooked teeth, and various other flaws of the teeth and jaw. Braces can be either cosmetic or structural. Dental braces are often used in conjunction with other orthodontic appliances to help widen the palate or jaws and to otherwise assist in shaping the teeth and jaws. Process The application of braces moves the teeth as a result of force and pressure on the teeth. There are traditionally four basic elements used: brackets, bonding material, arch wire, and ligature elastic (also called an “O-ring”). The teeth move when the arch wire puts pressure on the brackets and teeth. Sometimes springs or rubber bands are used to put ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nickel Titanium
Nickel titanium, also known as Nitinol, is a metal alloy of nickel and titanium, where the two elements are present in roughly equal atomic percentages. Different alloys are named according to the weight percentage of nickel; e.g., Nitinol 55 and Nitinol 60. It exhibits the shape memory effect and superelasticity at different temperatures. Nitinol alloys exhibit two closely related and unique properties: the shape memory effect and superelasticity (also called pseudoelasticity). Shape memory is the ability of Nitinol to undergo deformation at one temperature, stay in its deformed shape when the external force is removed, then recover its original, undeformed shape upon heating above its "transformation temperature". Superelasticity is the ability for the metal to undergo large deformations and immediately return to its undeformed shape upon removal of the external load. Nitinol can deform 10–30 times as much as ordinary metals and return to its original shape. Whether Nitinol be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raymond Begg
Percival Raymond Begg AO (10 October 1898 – 18 January 1983) was a professor at the University of Adelaide School of Dentistry and a well known orthodontist, famous for developing the "Begg technique".''Highest international honour for orthodontics pioneer'' University News & Events, 1 June 2007, University of Adelaide, retrieved 1 Feb 2009. Permanent displays dedicated to the Begg technique can be found in the in Washington DC, the Library of the American Dental Association in Chicago, and the PR Begg Museum at the University of Adelaide. Education Begg was born in[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retainer (orthodontic Device)
Orthodontic retainers are custom-made devices, usually made of wires or clear plastic, that hold teeth in position after surgery or any method of realigning teeth. Once a phase of orthodontic treatment has been completed to straighten teeth, there remains a lifelong risk of relapse (a tendency for teeth to return to their original position) due to a number of factors: recoil of periodontal fibres, pressure from surrounding soft tissues, the occlusion and patient’s continued growth and development. By using retainers to hold the teeth in their new position for a length of time, the surrounding periodontal fibres adapt to changes in the bone which can help minimize any changes to the final tooth position after the completion of orthodontic treatment. Retainers may also be used to treat overjets. Removable retainers Removable retainers include Hawley, Vacuum-formed, Begg and Barrer. They provide orthodontic retention when worn and they can be taken in and out of the mouth. They ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds. Oxygen is Earth's most abundant element, and after hydrogen and helium, it is the third-most abundant element in the universe. At standard temperature and pressure, two atoms of the element bind to form dioxygen, a colorless and odorless diatomic gas with the formula . Diatomic oxygen gas currently constitutes 20.95% of the Earth's atmosphere, though this has changed considerably over long periods of time. Oxygen makes up almost half of the Earth's crust in the form of oxides.Atkins, P.; Jones, L.; Laverman, L. (2016).''Chemical Principles'', 7th edition. Freeman. Many major classes of organic molecules in living organisms contain oxygen atoms, such as proteins, nucleic acids, carbohydrates, and fats, as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vulcanite
Vulcanite is a rare copper telluride mineral. The mineral has a metallic luster, and has a green or bronze-yellow tint. It has a hardness between 1 and 2 on the Mohs scale (between talc and gypsum). Its crystal structure is orthorhombic. Vulcanite is named for the place where it was discovered in 1961, the Mammoth Good Hope Mine in Vulcan (ghost town and district), Gunnison County, Colorado. Small deposits have also been discovered in Japan, Russia, Saudi Arabia, and Norway. It occurs with native tellurium, rickardite, petzite, and sylvanite. See also *Telluride mineral A telluride mineral is a mineral that has the telluride anion as a main component. Tellurides are similar to sulfides and are grouped with them in both the Dana and Strunz mineral classification systems.http://webmineral.com/strunz/II.shtml Webm ... References Telluride minerals Orthorhombic minerals Minerals in space group 59 Minerals described in 1961 {{mineral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piano Wire
Piano wire, or "music wire", is a specialized type of wire made for use in piano strings but also in other applications as springs. It is made from tempered high-carbon steel, also known as spring steel, which replaced iron as the material starting in 1834. Piano wire has a very high tensile strength to cope with the heavy demands placed upon piano strings; accordingly, piano wire is also used for a number of other purposes, including springs, surgical uses, and in special effects. History The oldest record of wire being made for musical instruments is from Augsburg in 1351.Dolge (1911, 124) Starting around 1800, the piano began to be built ever more ambitiously, with sturdier (eventually, iron) framing and greater string tension. This led to innovations in making tougher piano wire. In 1834, the Webster & Horsfal firm of Birmingham, United Kingdom brought out a form of piano wire made from cast steel; according to Dolge it was "so superior to the iron wire that the Englis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromium
Chromium is a chemical element with the symbol Cr and atomic number 24. It is the first element in group 6. It is a steely-grey, lustrous, hard, and brittle transition metal. Chromium metal is valued for its high corrosion resistance and hardness. A major development in steel production was the discovery that steel could be made highly resistant to corrosion and discoloration by adding metallic chromium to form stainless steel. Stainless steel and chrome plating (electroplating with chromium) together comprise 85% of the commercial use. Chromium is also greatly valued as a metal that is able to be highly polished while resisting tarnishing. Polished chromium reflects almost 70% of the visible spectrum, and almost 90% of infrared light. The name of the element is derived from the Greek word χρῶμα, ''chrōma'', meaning color, because many chromium compounds are intensely colored. Industrial production of chromium proceeds from chromite ore (mostly FeCr2O4) to produce ferro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon
Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent In chemistry, the valence (US spelling) or valency (British spelling) of an element is the measure of its combining capacity with other atoms when it forms chemical compounds or molecules. Description The combining capacity, or affinity of an ...—its atom making four electrons available to form covalent bond, covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes up only about 0.025 percent of Earth's crust. Three Isotopes of carbon, isotopes occur naturally, Carbon-12, C and Carbon-13, C being stable, while Carbon-14, C is a radionuclide, decaying with a half-life of about 5,730 years. Carbon is one of the Timeline of chemical element discoveries#Ancient discoveries, few elements known since antiquity. Carbon is the 15th Abundance of elements in Earth's crust, most abundant element in the Earth's crust, and the Abundance of the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Week 4 Of Braces
A week is a unit of time equal to seven days. It is the standard time period used for short cycles of days in most parts of the world. The days are often used to indicate common work days and rest days, as well as days of worship. Weeks are often mapped against yearly calendars, but are typically not the basis for them, as weeks are not based on astronomy. The modern seven-day week can be traced back to the Babylonians, who used it within Babylonian calendar, their calendar. Other ancient cultures had different week lengths, including ten in Ancient Egypt, Egypt and an eight-day week for Etruscan civilization, Etruscans. The Etruscan week was adopted by the Ancient Romans, but they later moved to a seven-day week, which had spread across Western Asia and the Eastern Mediterranean. In 321 AD, Emperor Constantine officially decreed a seven-day week in the Roman Empire, including making Sunday a public holiday. This later spread across Europe, then the rest of the world. In Engli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emil Herbst
Emil or Emile may refer to: Literature *''Emile, or On Education'' (1762), a treatise on education by Jean-Jacques Rousseau * ''Émile'' (novel) (1827), an autobiographical novel based on Émile de Girardin's early life *''Emil and the Detectives'' (1929), a children's novel *"Emil", nickname of the Kurt Maschler Award for integrated text and illustration (1982–1999) *''Emil i Lönneberga'', a series of children's novels by Astrid Lindgren Military *Emil (tank), a Swedish tank developed in the 1950s * Sturer Emil, a German tank destroyer People *Emil (given name), including a list of people with the given name ''Emil'' or ''Emile'' *Aquila Emil (died 2011), Papua New Guinean rugby league footballer Other * ''Emile'' (film), a Canadian film made in 2003 by Carl Bessai *Emil (river), in China and Kazakhstan See also * * *Aemilius (other) *Emilio (other) Emilio may refer to: * Emilio Navaira, a Mexican-American singer often called "Emilio" * Emilio Piazza M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
